This invention relates to a liquid crystal display, and more particularly to, a liquid crystal display that has enhanced vibration-proof characteristic and shock-proof characteristic, and that guarantees a quality of image by preventing the orientation characteristic of liquid crystal molecule from deteriorating even when the liquid crystal display is subject to a deformation by external stress.
In conventional liquid crystal displays, the liquid crystal panel has been fixed to the housing by applying double-side adhesive tape or adhesive agent to a width, which is as short as 1 mm, from the edge of image display region in the liquid crystal panel to the end of the liquid crystal panel. However, in liquid crystal displays used in harsh conditions, such as liquid crystal display in automobile""s navigation system and liquid crystal display in operating panel of industrial machine, the above fixing method does not give the satisfactory vibration-proof characteristic and shock-proof characteristic. Namely, there is a problem that the liquid crystal panel is dislocated or deformed due to vibration or shock, thereby a quality of image is deteriorated so that the display performance lowers.
Japanese patent application laid-open No.09-329777 (1997) discloses a liquid crystal display that offers a solution to the above problem. FIG. 1 shows an example of structure disclosed in Japanese patent application laid-open No.09-329777. In this structure, spaces A3 and A4 nearly sealed are provided by disposing frame-shaped elastic members 33 and 35 along the edge of front and back faces of a liquid crystal panel P, and the liquid crystal panel is fixed using the elasticity of the elastic members and the air-damping effect of the sealed spaces. Thus, the liquid crystal panel can be protected from being dislocated and deformed due to vibration and shock.
However, in the conventional structures including the above example, although they offer high vibration-proof characteristic and shock-proof characteristic in normal use, when static external stress such as user""s operation force is applied to the liquid crystal display, there occurs a deformation in the liquid crystal panel. This is because, to such static deformation stress, the air-damping effect is not available.
Also, since the liquid crystal panel is fixedly bound by the elastic members, the deformation of the housing itself, which supports the liquid crystal panel indirectly, is likely to be transmitted to the liquid crystal panel. As a result, due to the static external stress applied to the liquid crystal display, the liquid crystal panel is subject to a deformation. If the liquid crystal panel is deformed, then disorder in orientation of liquid crystal molecule in the liquid crystal panel occurs and therefore causes part of light and shade like a wave pattern in the display region due to unevenness in the amount of light transmitted. Thus, in the conventional liquid crystal displays, there is a problem that the static external stress causes deterioration in the quality of image.
Further, in the conventional liquid crystal display, since the elastic members are disposed adjacent to the display region of liquid crystal panel, even a slight deformation is likely to be transmitted to the display region of liquid crystal panel through the elastic members supporting the liquid crystal panel. Therefore, part of light and shade may occur in the display region and the quality of image may deteriorate.
Accordingly, it is an object of the invention to provide a liquid crystal display that has enhanced vibration-proof characteristic and shock-proof characteristic, and that guarantees a quality of image by preventing the orientation characteristic of liquid crystal molecule from deteriorating even when the liquid crystal display is subject to a deformation by external stress.
According to the invention, a liquid crystal display, comprises:
a housing; and
a liquid crystal panel which comprises a first substrate and a second substrate each of which has a nearly line-symmetrical and planar form and which have a nearly equal surface area and at least one of which are transparent, the first substrate and second substrate being nearly parallel disposed sandwiching a liquid crystal composition layer;
wherein the first substrate is provided with mounting end regions that are extended outside from the end of the second substrate at the line-symmetrical position of the first substrate, so that the liquid crystal panel is fixed to the housing through the mounting end regions.
In this invention, the mounting end regions composed of only the first substrate has a rigidity lower than part where the first and second substrates are overlapped to form an image display section with the liquid crystal composition layer sandwiched therebetween. Therefore, when the housing is deformed by static external stress, only the mounting end regions with the lower rigidity are deformed, thereby preventing the display section in the liquid crystal panel from being deformed. Further, owing to the gap provided between the liquid crystal panel and the housing, even when the housing is deformed by external stress, it can be avoided that the housing contacts the liquid crystal panel thereby causing a deformation in the liquid crystal panel. Also, by providing a sufficient adhesion width on the back surface of the extended part and securely fixing the liquid crystal panel to the housing with the adhesive means, it is avoided that the liquid crystal panel is dislocated or deformed due to vibration or shock.
Thus, in the liquid crystal display of the invention, against static weight, vibration or shock, the liquid crystal panel can be prevented from being dislocated or deformed. Namely, the quality of image in the liquid crystal display can be guaranteed even when static weight, vibration or shock is applied thereto.